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Turbo Direct Project 875 Rearend - 4-Wheel & Off-Road Magazine

Christian Lee Contributor

How many Toyota 4x4 owners have pushed their vehicles to the limit only to discover a handful of greasy chunks of metal when they pull the third member off the rearend to find out what that mysterious noise is all about? According to Kevin Norris of Turbo Direct, a lot of them have. For a number of years, Norris cleaned up on rebuilding the steady flow of Toyota rearends, but then he realized that simply replacing the gears was only a bandage on a much larger problem: Factory Toyota rearends aren't made to withstand the rigors that most serious four-wheelers put them through. An easy enough problem to diagnose, but the remedy? Simpler (not to mention more ingenious) than you might imagine.

Turbo Direct's Project 875 Drivetrain system is a bulletproof replacement rearend assembly. The unit uses stock Toyota axle tubes, so all of the factory flanges, spring perches, brake lines, and emergency-brake brackets are already in place, making the Project 875 a direct fit into your Toyota. The heart and soul of the Project 875 is the new housing, which holds a Chrysler 8 3/4-inch centersection. Turbo Direct jig-welds the housings to the Toyota axle tubes to create a unit that has been used successfully in 400-plus horsepower and 400-plus lb-ft of torque conditions.

Norris and his partner, Bob Morris, made a special trip down to our neck of the woods to show us their product and watch as 4 Wheel Parts Wholesalers installed a Project 875 into a '91 Toyota 4x4. Even at first glance we were impressed, but after witnessing the basic (and quick) installation, not to mention driving on the end product, we were astonished. With one exception, the Project 875 looked and felt like its factory counterpart. Good news for Toyota owners-that exception is that the Project 875 is bulletproof.

PhotosView Slideshow Problem: Toyota truck owners are not strangers to this view. While overseeing the installation of the Project 875 rearend from Turbo Direct, we counted more than five Toyota factory rearends in the 4 Wheel Parts Wholesalers scrap pile.

Problem: Toyota truck owners are not strangers to this view. While overseeing the installation of the Project 875 rearend from Turbo Direct, we counted more than five Toyota factory rearends in the 4 Wheel Parts Wholesalers scrap pile.

Solution: After repeatedly rebuilding Toyota rearends only to see them blow out time and again, Kevin Norris of Turbo Direct went to the root of the problem and solved it with the design of the Project 875 replacement rearend assembly. The unit is a direct fit into most Toyota trucks and utilizes a Chrysler 8 3/4-inch third member.

The size difference is great between the factory Toyota third member and the Chrysler model used in the Project 875 rearend. The complete assembly from Turbo Direct includes a new ring-and-pinion, bearings, new spider gears, a new seal kit already installed, and a new gasket and crush sleeve.

Pictured here are the internals that tend to cause the most problems in OE Toyota axles-broken teeth on the ring-and-pinion and significant wear to the cross-shaft in the spider gear.

By using larger-diameter gearsets and heavier-duty spider gears, the Project 875 virtually eliminates these problems.

The team at 4 Wheel Parts Wholesalers thought they were looking at an all-day venture when we asked them if they'd pull the factory rear axle and swap in the Turbo Direct model. But the Project 875 didn't require any more time to install than it took to tear out the stock axle.

The only necessary items that Turbo Direct doesn't provide for the swap are the U-joints. The company has found that it's easier to just provide the part number for the customer. The required U-joint is a common item and can be ordered from many parts outlets. Once you have the U-joint, you'll need to find a qualified driveshaft shop to mate the Chrysler and Toyota ends to a new shaft.

The guys at 4 Wheel Parts Wholesalers were able to pull the factory rearend in less than an hour. Although the Project 875 is a direct fit and you can easily install it yourself, a vehicle lift is great assistance. Turbo Direct charges a refundable rearend core charge as part of the price of the Project 875 and suggests that you send the OE housing in the same crate in which you received the new one.

With the old assembly out of the way, we simply positioned the new one under the vehicle and bolted it in. The Project 875 uses the OE axle tubes, so the spring perches, brake line, and emergency-brake brackets are already in place. Turbo Direct had our unit finished with black paint by MRH Auto Restoration, although the rearend can be painted or powdercoated any color.

With the new assembly in place and the spring bolts tightened, the 4 Wheel Parts crew fastened the brake components to their original location. Installing the new axle took less time than it did to pull the old one. The majority of our time was spent waiting for the new driveshaft to be fabricated, although you could have that step completed beforehand and be back on the road in just a few hours.

The axleshafts slid into the axle tubes and met the third member without a problem. The only job here was to tighten the four bolts per side, reattach the shocks, and mount up the wheels. Turbo Direct is currently working on assemblies that will replace the factory ones in Toyota Land Cruisers, using components from Chevy Blazers. The company also says that some of its products will work in early-model Willys.

After the rearend was fully installed, we added gear oil. Once the driveshaft is bolted up, Turbo Direct recommends driving for about 30 minutes on surface streets to let the gears warm up before hopping on the highway or hitting the dirt. We've put more than 1,000 miles on in less than three weeks and haven't discovered any problems. In fact, it drives no differently from the OE rearend. Another plus of the Project 875 is that virtually no ground clearance is lost as compared to the Toyota axle, and it actually affords more clearance than a Ford 9-inch or Dana 60.

The Project 875 is offered standard with 4.10 gears, limited slip, or lockers. This one came equipped with the specially designed ARB unit already installed, leaving only the compressor and switch to be hooked up.

The compressor was positioned under the hood. We like that there is an extra air jack on the compressor, which we plan to attach a male connection to. The compressor maintains about 85-100 psi constantly, so airing up tires after a run should be a cinch.

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Turbo Direct Project 875 Rearend - 4-Wheel & Off-Road Magazine

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